ATLANTA (AP) _ The road to Jimmy Carter's presidential library and policy center is strewn with roadblocks, including opponents chaining themselves to trees and a lawsuit that claims the road would destroy city neighborhoods.

Although construction of the $25 million library has not halted, the battle over the 2.4-mile, four-lane parkway, which Carter has said is ''closely tied'' to his complex, has escalated in recent weeks.

At least nine people have been arrested on unlawful assembly, disorderly conduct and other charges for attempting to disrupt construction of the limited-access road stretching northeastward from Atlanta's downtown expressway.

The battle has been going on since the parkway - dubbed the ''Ex-Pres-Way'' by opponents - was first proposed in late 1981.

The major portion of the parkway would follow a right-of-way acquired during the 1960s and early 1970s for construction of a freeway spur that was later abandoned. Only one residence stands in the parkway's path, which goes through the Druid Hill Historic District and several other neighborhoods popular with young people who have returned to the city.

Carter has tried to remain detached from the road controversy. In a deposition for one of the lawsuits against the road, the former president said he originally took no position, but eventually supported the road because it was a ''feasible approach that protected the quality of the neighborhoods as best it could and still meet our needs for access from the east and west.''

Even now, despite Carter's oft-repeated belief that the road and library are inseparable, his spokesmen refer questions about the road to the state Department of Transportation.

The two principal organizations opposing the parkway are CAUTION Inc. - Citizens Against Unnecessary Thoroughfares In Older Neighborhoods - and a newly created group called The Road Busters.

In the words of Road Busters' spokeswoman Sharman Colosetti: ''We do the direct action; they (CAUTION) do the legal work. We're training people in civil disobedience.''

Last month The Road Busters began a series of demonstrations designed to prevent construction of the road. After climbing a tree and unfurling a banner which said ''Save Our Parks,'' four people were arrested when they refused to leave.

Last week, five more people were arrested, and construction on the road temporarily was halted, after protesters chained themselves to trees in a park that would be affected by the parkway.

Four of those arrested had trespassing charges against them dismissed because the judge said it wasn't clear who owned the land they were on.

The major legal challenges are lawsuits filed by the National Trust for Historic Preservation and CAUTION, which also took out full-page ads in Atlanta newspapers urging Carter to abandon his support of the parkway.

In a lawsuit filed last year, CAUTION, made up largely of professional people who live near the road, claimed the road was the product of a deal between Carter and state Transportation Commissioner Tom Moreland.

The lawsuit claimed statistics were juggled to make it appear the road was needed to relieve traffic congestion, environmental effects were ignored or glossed over and opponents did not receive sufficient opportunity to register complaints.

The suit claims the road would do irreparable damage to several small, neighborhood parks designed by Frederick Law Olmstead, the landscape architect who also designed New York's Central Park and the U.S. Capitol grounds.

Following a hearing in October, U.S. District Judge William C. O'Kelley dismissed the lawsuit, saying the federal and state agencies ''acted reasonably and in good faith objectivity, even though at times certain conduct may have been less than praiseworthy.''

CAUTION appealed O'Kelley's decision to the 11th U.S. Circuit Court of Appeals which will hear arguments today.CAUTION asked the 11th Circuit to change the panel scheduled to hear arguments because Carter appointed two of the three judges, but the court refused.

City politics also became involved in the controversy when it was revealed that Atlanta City Council President Marvin Arrington was a subcontractor on the $22 million road project when the council voted last November to complete a needed transfer of land between the city and the state.

Arrington withdrew as a subcontractor in December after Georgia Attorney General Michael Bowers issued an opinion saying Arrington's participation was a conflict of interest. But the opinion said that did not invalidate the council action.

According to parkway plans, the east- and west-bound lanes of the limited- access road would divide about a mile from downtown; the Carter complex would be located in the middle on a 31-acre tract. Jogging and bicycle paths would follow the road along most of its length; parks and picnic areas would also be included.

Construction on the library complex began Oct. 2, 1984, with Carter calling it ''a million-dollar gamble'' because of the lawsuits which, if successful, ''would obviously make the whole project very doubtful.''

The complex is supposed to open Jan. 1, 1986.

In addition to a library and museum, plans include The Carter Center of Emory University, a think-tank where the former president will hold discussions of major issues. Sessions on the Middle East and health policy already have been held, and a conference on arms control is planned for April.

Although the Carter Center is not named in the CAUTION lawsuit, Carter spokesman Dan Lee declined an interview, citing attorneys' advice not to talk about the project while the suit was pending.

The controversy is not the first to face former presidents seeking to build libraries.

A major battle surrounded Richard Nixon's desire to locate his library at Duke University, where he attended law school. That proposal was rejected and the library is now scheduled to be built at Nixon's former home at San Clemente, Calif.